Detection method for sensor membrane of europium titanium oxide as part of a biosensor by using PNIPAAm for wrapping enzymes

Abstract

A detection method for a sensor membrane formed of europium titanium oxide as part of a biosensor by using PNIPAAm for wrapping enzymes includes adding 1.0 g of NIPAAm powder to 20 ml water, heating same at 60° C. to form NIPAAm solution, and cooling the NIPAAm solution; adding 200 μl of 98.7 wt % of APS and 50 μl of 99 wt % of TEMED to the NIPAAm solution, uniformly mixing same, and reacting the mixture for 30 hours to prepare a transparent, gel PNIPAAm; adding 5 mg enzymes to 100 μl of 1×PBS buffer solution, uniformly mixing same, adding 100 μl of PNIPAAm to the buffer solution, and uniformly mixing the buffer solution; placing a biosensor on a heater for heating at a constant temperature of 37° C. with the biosensor being an EIS sensor having a sensor membrane formed of EuTi x O y ; and taking a measurement.

What is claimed is: 
     
       1. A detection method comprising:
 (1) adding 1.0 g of N-isopropylacrylamide (NIPAAm) powder to 20 ml water, heating at 60° C. to form a NIPAAm solution, and cooling the NIPAAm solution to room temperature; 
 (2) adding 200 μl of 98.7 wt % of ammonium peroxodisulfate (APS) and 50 μl of 99 wt % of N,N,N,N-tetramethylethylenediamine (TEMED) to the NIPAAm solution, uniformly mixing it to form a mixture, and reacting the mixture for 30 hours at room temperature to prepare a transparent gel, poly-N-isopropylacrylamide (PNIPAAm); 
 (3) adding 5 mg enzymes to 100 μl of 1×PBS buffer solution, uniformly mixing it, adding 100 μl of the transparent gel, PNIPAAm to the buffer solution, and uniformly mixing the buffer solution; 
 (4) placing a biosensor on a heater for heating at a constant temperature of 37° C., wherein the biosensor is an Electrolyte-insulator-Semiconductor (EIS) sensor having a sensor membrane formed of europium titanium oxide; 
 (5) dropping 25 μl of the buffer solution on the sensor membrane of the biosensor for wrapping the enzymes on the sensor membrane of the biosensor; 
 (6) heating and curing the wrapped biosensor to form a white gel on the sensor membrane; 
 (7) placing the biosensor in a solution kept at 37° C. and keeping the white gel obtained at step (6) at 37° C.; and 
 (8) taking a measurement. 
 
     
     
       2. The detection method of  claim 1 , wherein the biosensor is configured to detect glucose, urea, lactic acid, or uric acid.